Investigators were also raiding 18 properties in Berlin, including 10 apartments as well as garages and vehicles, police and prosecutors said in a statement.
“The measures today are focused on the search for the stolen art treasures and possible evidence, such as data storage media, clothing and tools,” they said.
In what local media have described as the biggest art heist in modern history, the robbers had launched their brazen raid on Green Vault museum in Dresden's Royal Palace on November 25th, 2019.
Having initiated a partial power cut and broken in through a window, they snatched priceless 18th-century jewellery from the collection of the Saxon ruler August the Strong.
Items stolen included a sword whose hilt is encrusted with nine large and 770 smaller diamonds, and a shoulderpiece which contains the famous 49-carat Dresden white diamond, Dresden's Royal Palace had said.
Dramatic CCTV footage released at that time showed one of the robbers breaking into a display case with an axe.
Police hunting for the suspects had launched several appeals, offering up to half a million euros in reward for information leading to their arrests.
On Monday, around 1,600 officers were deployed in the raids and arrests, with special reinforcements called in from across the country to help.
Police did not identify the three arrested, but said they are German citizens.
All three are accused of “serious gang robbery and two counts of arson,” said Dresden prosecutors.
100-kg gold coin
Germany has been hit by several high-profile heists, with banks and museums frequent targets.
A Berlin court sentenced three men to multi-year jail sentences in February for the theft of a 100-kilogram gold coin from one of the German capital's museums.
Police have found no trace of the Canadian coin since the late-night heist in March 2017 from the Bode Museum, located close to Chancellor Angela Merkel's Berlin apartment.
The “Big Maple Leaf”, one of five minted in 2007, is considered the world's second largest gold coin after the one-tonne Australian Kangaroo issued in 2012.
Robbers also hit a German customs office early November, making off with €6.5 million in cash.
Police have offered €100,000 in reward for information leading to the arrest and/or conviction of the suspects.